Refactored the loadProject system to make loading of statistical cases work as they should.
Got the update of references regarding grid and unionActive cells work
Introduced a bool to keep track of what cell results to store.
Introduced a clear method in ActiveCellInfo.
Renamed a bit
p4#: 21036
Invalidate existing statisticsCases when adding/removing source cases
Moved computation of active cell union from RigStatistics to RimIdenticalGridCaseGroup
Recompute active cell union when opening project file
p4#: 21023
This does not yet compile due to a unfortunate mix of perforce, cmake setup and unit_test project shortcomings.
Need to move RigStatistics into ProjectDataModel and rename it before this is running again.
p4#: 20945
